AExE01 · Chapter 1Programming & Applications🏛️ Past Licensure QuestionID: 8fe78f2c
For a Class B transistor power amplifier, where is the DC operating quiescent point (Q-point) positioned on the load line?
For a Class B transistor power amplifier, where is the DC operating quiescent point (Q-point) positioned on the load line?
Multiple Choice Options
- A
In the middle of the active region
- B
Deep in the saturation region
- C✓ Correct Option
Exactly at the cut-off point on the DC load line
- D
At the breakdown threshold
Detailed Technical Solution & Explanation
In a Class B amplifier, the quiescent current is zero (). The Q-point is intentionally biased exactly at the cut-off point on the load line so that the transistor conducts for only one half () of the input signal cycle.
Option Analysis:
•
Option A (In the middle of the active region): Class A amplifier bias point (for maximum symmetrical swing).
•
Option B (Deep in the saturation region): Inverter/switching transistor state, not linear amplifier Q-point.
•
Option C (Exactly at the cut-off point on the D...): Correct. Defines the operating bias of Class B amplification.
•
Option D (At the breakdown threshold): Causes device failure.
Reference: Mock Test 04NEC Licensure Syllabus